Glycosyl urea

Khorlin and coworkers92 95 reported that the reaction of isothiocyanates 2 and 53 with acetic acid, as well as benzoic acid, in the presence of triethyl-amine, leads to the formation of N-glycosylacetamides 175 or 176 in 35% yield, and, as coproducts, l,3-bis(glycosyl)ureas (177 and 179) and 1,3-bis(glycosyl)thioureas (178 and 180). This method has been employed in... 

Pinter s and Ichikawa s groups have used 73 (Scheme 18) for the synthesis of W-glycosyl ureas 74 in high yield in DMF [83] and in water [81, 84,85] in spite of the relative sensitivity of 73 to water. Following the same methodology, cellobiosyl and lactosyl azides 81 and 82 were transformed (Scheme 20) into the corresponding disaccharide oxazolidinones 83 and 84, which were used for the preparation of urea-tethered pseudooligosaccharides 85 and 86 [81]. 

FIGURE 15.3 Methods for selective formation of glycosyl ureas. 

STEREOSELECTIVE SYNTHESIS OF GLYCOSYL UREAS FROM glycal TRICHLOROACETIMIDATES... 

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